I didn't like it because the original melody that it was inspired by was changed so much that it was almost unrecognizable and didn't sound very good. I really like the original tune, but this didn't have the catchyness or energy that made the original so great. It may have been the way the tune was rearranged, or it might have been how it felt fairly anticlimatic. I waited for the climax to come, but it never did. I actually told the song to "do something" near the end of the song because it was getting boring.
I have 3 other songs by GrayLightning, but I don't like this one that much. I would say that this is really well done and the instruments are well sampled and such, and I'm sure a lot of effort was put into it.
EDIT: Basically, I didn't like how he rearranged the song. I thought it sounded pretty bland and boring without any melody.